certificates/cmd/step-ca/main.go
Anton Lundin 3e6137110b Add support for using ssh-agent as a KMS
This adds a new KMS, SSHAgentKMS, which is a KMS to provide signing keys
for issuing ssh certificates signed by a key managed by a ssh-agent. It
uses the golang.org/x/crypto package to get a native Go implementation
to talk to a ssh-agent.

This was primarly written to be able to use gpg-agent to provide the
keys stored in a YubiKeys openpgp interface, but can be used for other
setups like proxying a ssh-agent over network.

That way the signing key for ssh certificates can be kept in a
"sign-only" hsm.

This code was written for my employer Intinor AB, but for simplicity
sake gifted to me to contribute upstream.

Signed-off-by: Anton Lundin <glance@acc.umu.se>
2020-11-04 09:06:23 +01:00

188 lines
5.8 KiB
Go

package main
import (
"flag"
"fmt"
"html"
"log"
"math/rand"
"net/http"
"os"
"reflect"
"regexp"
"strconv"
"time"
// Server profiler
_ "net/http/pprof"
"github.com/smallstep/certificates/authority"
"github.com/smallstep/certificates/commands"
"github.com/urfave/cli"
"go.step.sm/cli-utils/command"
"go.step.sm/cli-utils/command/version"
"go.step.sm/cli-utils/config"
"go.step.sm/cli-utils/usage"
// Enabled kms interfaces.
_ "github.com/smallstep/certificates/kms/awskms"
_ "github.com/smallstep/certificates/kms/cloudkms"
_ "github.com/smallstep/certificates/kms/softkms"
_ "github.com/smallstep/certificates/kms/sshagentkms"
// Experimental kms interfaces.
_ "github.com/smallstep/certificates/kms/yubikey"
// Enabled cas interfaces.
_ "github.com/smallstep/certificates/cas/cloudcas"
_ "github.com/smallstep/certificates/cas/softcas"
)
// commit and buildTime are filled in during build by the Makefile
var (
BuildTime = "N/A"
Version = "N/A"
)
func init() {
config.Set("Smallstep CA", Version, BuildTime)
authority.GlobalVersion.Version = Version
rand.Seed(time.Now().UnixNano())
}
// appHelpTemplate contains the modified template for the main app
var appHelpTemplate = `## NAME
**{{.HelpName}}** -- {{.Usage}}
## USAGE
{{if .UsageText}}{{.UsageText}}{{else}}**{{.HelpName}}**{{if .Commands}} <command>{{end}} {{if .ArgsUsage}}{{.ArgsUsage}}{{else}}_[arguments]_{{end}}{{end}}{{if .Description}}
## DESCRIPTION
{{.Description}}{{end}}{{if .VisibleCommands}}
## COMMANDS
{{range .VisibleCategories}}{{if .Name}}{{.Name}}:{{end}}
|||
|---|---|{{range .VisibleCommands}}
| **{{join .Names ", "}}** | {{.Usage}} |{{end}}
{{end}}{{if .VisibleFlags}}{{end}}
## OPTIONS
{{range $index, $option := .VisibleFlags}}{{if $index}}
{{end}}{{$option}}
{{end}}{{end}}{{if .Copyright}}{{if len .Authors}}
## AUTHOR{{with $length := len .Authors}}{{if ne 1 $length}}S{{end}}{{end}}:
{{range $index, $author := .Authors}}{{if $index}}
{{end}}{{$author}}{{end}}{{end}}{{if .Version}}{{if not .HideVersion}}
## ONLINE
This documentation is available online at https://smallstep.com/docs/certificates
## VERSION
{{.Version}}{{end}}{{end}}
## COPYRIGHT
{{.Copyright}}
## FEEDBACK ` +
html.UnescapeString("&#"+strconv.Itoa(128525)+";") + " " +
html.UnescapeString("&#"+strconv.Itoa(127867)+";") +
`
The **step-ca** utility is not instrumented for usage statistics. It does not phone home.
But your feedback is extremely valuable. Any information you can provide regarding how you’re using **step-ca** helps.
Please send us a sentence or two, good or bad: **feedback@smallstep.com** or https://github.com/smallstep/certificates/discussions.
{{end}}
`
func main() {
// Override global framework components
cli.VersionPrinter = func(c *cli.Context) {
version.Command(c)
}
cli.AppHelpTemplate = appHelpTemplate
cli.SubcommandHelpTemplate = usage.SubcommandHelpTemplate
cli.CommandHelpTemplate = usage.CommandHelpTemplate
cli.HelpPrinter = usage.HelpPrinter
cli.FlagNamePrefixer = usage.FlagNamePrefixer
cli.FlagStringer = stringifyFlag
// Configure cli app
app := cli.NewApp()
app.Name = "step-ca"
app.HelpName = "step-ca"
app.Version = config.Version()
app.Usage = "an online certificate authority for secure automated certificate management"
app.UsageText = `**step-ca** <config> [**--password-file**=<file>] [**--resolver**=<addr>] [**--help**] [**--version**]`
app.Description = `**step-ca** runs the Step Online Certificate Authority
(Step CA) using the given configuration.
See the README.md for more detailed configuration documentation.
## POSITIONAL ARGUMENTS
<config>
: File that configures the operation of the Step CA; this file is generated
when you initialize the Step CA using 'step ca init'
## EXIT CODES
This command will run indefinitely on success and return \>0 if any error occurs.
## EXAMPLES
These examples assume that you have already initialized your PKI by running
'step ca init'. If you have not completed this step please see the 'Getting Started'
section of the README.
Run the Step CA and prompt for password:
'''
$ step-ca $STEPPATH/config/ca.json
'''
Run the Step CA and read the password from a file - this is useful for
automating deployment:
'''
$ step-ca $STEPPATH/config/ca.json --password-file ./password.txt
'''`
app.Flags = append(app.Flags, commands.AppCommand.Flags...)
app.Flags = append(app.Flags, cli.HelpFlag)
app.Copyright = "(c) 2018-2020 Smallstep Labs, Inc."
// All non-successful output should be written to stderr
app.Writer = os.Stdout
app.ErrWriter = os.Stderr
app.Commands = command.Retrieve()
// Start the golang debug logger if environment variable is set.
// See https://golang.org/pkg/net/http/pprof/
debugProfAddr := os.Getenv("STEP_PROF_ADDR")
if debugProfAddr != "" {
go func() {
log.Println(http.ListenAndServe(debugProfAddr, nil))
}()
}
app.Action = func(_ *cli.Context) error {
// Hack to be able to run a the top action as a subcommand
set := flag.NewFlagSet(app.Name, flag.ContinueOnError)
set.Parse(os.Args)
ctx := cli.NewContext(app, set, nil)
return commands.AppCommand.Run(ctx)
}
if err := app.Run(os.Args); err != nil {
if os.Getenv("STEPDEBUG") == "1" {
fmt.Fprintf(os.Stderr, "%+v\n", err)
} else {
fmt.Fprintln(os.Stderr, err)
}
os.Exit(1)
}
}
func flagValue(f cli.Flag) reflect.Value {
fv := reflect.ValueOf(f)
for fv.Kind() == reflect.Ptr {
fv = reflect.Indirect(fv)
}
return fv
}
var placeholderString = regexp.MustCompile(`<.*?>`)
func stringifyFlag(f cli.Flag) string {
fv := flagValue(f)
usage := fv.FieldByName("Usage").String()
placeholder := placeholderString.FindString(usage)
if placeholder == "" {
switch f.(type) {
case cli.BoolFlag, cli.BoolTFlag:
default:
placeholder = "<value>"
}
}
return cli.FlagNamePrefixer(fv.FieldByName("Name").String(), placeholder) + "\t" + usage
}